U.S. patent number 7,915,758 [Application Number 12/257,367] was granted by the patent office on 2011-03-29 for printed circuit board and method for determining an optimization point for sensing a voltage regulator module on a printed circuit board.
This patent grant is currently assigned to Hon Hai Precision Industry Co., Ltd.. Invention is credited to Duen-Yi Ho, Shou-Kuo Hsu.
United States Patent |
7,915,758 |
Ho , et al. |
March 29, 2011 |
Printed circuit board and method for determining an optimization
point for sensing a voltage regulator module on a printed circuit
board
Abstract
A print circuit board (PCB) includes a voltage regulator module
(VRM), a plurality of loads, and a sense location for augmenting
the voltage margin of the loads. The VRM is configured for charging
the loads. Each load has a weight. The voltage value of the sense
location equals to a summation of a corresponding weight value of a
corresponding load multiplied by a corresponding voltage value of
the load, for each of the plurality of loads on the PCB. An
optimization method for the sense location on the PCB is also
provided.
Inventors: |
Ho; Duen-Yi (Taipei Hsien,
TW), Hsu; Shou-Kuo (Taipei Hsien, TW) |
Assignee: |
Hon Hai Precision Industry Co.,
Ltd. (Tu-Cheng, Taipei Hsien, TW)
|
Family
ID: |
41724240 |
Appl.
No.: |
12/257,367 |
Filed: |
October 23, 2008 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20100052422 A1 |
Mar 4, 2010 |
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Foreign Application Priority Data
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Aug 29, 2008 [CN] |
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2008 1 0304298 |
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Current U.S.
Class: |
307/32 |
Current CPC
Class: |
H05K
1/0262 (20130101); H05K 1/141 (20130101); H05K
1/0268 (20130101); H05K 1/181 (20130101) |
Current International
Class: |
H02J
3/12 (20060101) |
Field of
Search: |
;307/32,69
;323/234,285,267,268 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Paladini; Albert W
Attorney, Agent or Firm: Ma; Zhigang
Claims
What is claimed is:
1. A printed circuit board (PCB), comprising: a plurality of loads;
a voltage regulator module (VRM) for providing voltage for each of
the plurality of loads; and a point for sensing the VRM for each of
the plurality of loads; wherein each load from the plurality of
loads has a weight value based on current values of the plurality
of loads or the number of the plurality of loads, wherein a voltage
value at the point for sensing the VRM equals to a summation of a
corresponding weight value of a corresponding load multiplied by a
corresponding voltage value of the corresponding load, for each of
the plurality of loads on the PCB.
2. The PCB of claim 1, wherein the corresponding weight value of
the corresponding load equals to a current value of the
corresponding load divided by a sum of current values of each of
the plurality of loads.
3. The PCB of claim 1, wherein the corresponding weight value of
the corresponding load equals to a current square value of the
corresponding load divided by a sum of current square values of
each of the plurality of loads.
4. The PCB of claim 1, wherein the corresponding weight value of
the corresponding load equals to one divided by the number of the
plurality of loads.
5. A method for determining an optimization point for sensing a
voltage regulator module (VRM) on a printed circuit board (PCB),
comprising of: obtaining voltage values for one or more loads based
on current values of the one or more loads on the PCB; calculating
weight values for the one or more loads based on the current values
of the one or more loads on the PCB or the number of the one or
more loads; calculating a summation of a corresponding weight value
of a corresponding load multiplied by a corresponding voltage value
of the corresponding load, for each of the one or more loads on the
PCB; and determining the optimization point for sensing the VRM on
the PCB according to the summation.
6. The method of claim 5, wherein calculating a current value of
the corresponding load is divided by a sum of current values of
each of the one or more of loads as the corresponding weight value
of the corresponding load.
7. The method of claim 5, wherein calculating a current square
value of the corresponding load divided by a sum of current square
values of each of one or more loads as the corresponding weight
value of the corresponding load.
8. The method of claim 5, wherein calculating one divided by the
number of the one or more loads as the corresponding weight value
of the corresponding load.
Description
BACKGROUND
1. Field of the Invention
The present invention relates to a printed circuit board (PCB), and
particularly to a method for determining an optimization point for
sensing a voltage regulator module on the PCB.
2. Description of Related Art
PCBs have played an important role in electrical production.
Generally, a PCB can have a number of voltage regulator modules
(VRMs) for charging one or more loads on the PCB. PCB designers
need to sense a voltage at a point near the VRM to feedback the
voltage of the VRM, for making the VRM supplies the correct voltage
for the loads. A voltage at the point equals to a voltage of the
corresponding VRM. The point for sensing the VRM further acts as a
mirror voltage source of the corresponding VRM, which affects
voltage distribution on the PCB, and charges one or more loads on
the PCB. The point affects performance of the corresponding VRM. An
appropriate point for sensing the voltage of the VRM can augment
voltage margins of the loads. PCB designers generally determine a
point for sensing the voltage of a VRM manually, which generally
cannot improve a performance of the corresponding VRM, and cannot
augment the voltage margin of the loads.
What is needed, therefore, is a PCB and a method for determining an
optimization point for sensing a VRM on the PCB that can amend the
aforementioned deficiency.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a PCB built in a simulation
environment.
FIG. 2 is a flowchart of an exemplary method for determining an
optimization point for sensing a VRM on a PCB.
FIG. 3 is a schematic diagram of an exemplary PCB.
DETAILED DESCRIPTION
Referring to FIGS. 1-2, an exemplary method for determining an
optimization point for sensing a VRM on a printed circuit board
(PCB) may include following blocks. Depending on the embodiment,
additional blocks may be added, others deleted, and the ordering of
the blocks may be changed.
In block S101, a layout of a PCB 100 may be simulated using a
simulation software. A detailed explanation of one exemplary
embodiment of determining an optimization point for sensing a
voltage regulator module (VRM) on the PCB 100 is detailed below.
However, it may be understood that the embodiment is exemplary and
may be used for other PCBs with different configurations. In the
illustrated embodiment, the PCB 100 includes a VRM 200, and three
loads C1, C2, and C3, such as a resistor, capacitor, inductor,
and/or transistor, for example. The point for sensing the VRM 200
is marked as "D" in FIG. 1. The voltage of the VRM 200 is 1.5 volts
(V) in one exemplary embodiment. The initialization position of
point D for sensing the VRM 200 can be arbitrary. In one
embodiment, the point D is positioned adjacent to the VRM 200,
however, the location of the point D is not limited thereto. An
output voltage scope of the VRM 200 ranges from about 1.425V to
about 1.575 V in one exemplary embodiment. The VRM 200 provides
voltage for the loads C1, C2, and C3, and sets the voltage value of
the point D as about 1.5V. Parameters I1, I2, and I3 act as current
values of the loads C1, C2, and C3 respectively. Parameters V1, V2,
and V3 act as voltage values of the loads C1, C2, and C3
respectively. Afterwards, the current values I1, I2, and I3 are set
as about 2.6 amperes (A), about 9.6 A and about 2.38 A
respectively, the voltage values V1, V2, and V3 are equal to about
1.4697V, about 1.4599V, and about 1.4595V respectively. Therefore,
a voltage margin of the load C1 is a difference between the voltage
value V1 and the least voltage value 1.425V of the VRM 200, i.e.
about 44.7 millivolts (mV). A voltage margin of the load C2 is a
difference between the voltage value V2 and the least voltage value
about 1.425V of the VRM 200, i.e. about 34.9 mV. A voltage margin
of the load C3 is a difference between the voltage value V3 and the
least voltage value about 1.425V of the VRM 200, i.e. about 34.5
mV.
In block S102, weight values for the loads C1, C2, and C3 are
calculated according to a weighted average method. In one
embodiment, normalization values of the load current values I1, I2,
and I3 are set as the corresponding load weight values which are
calculated as follows:
.times..times..times..times..times..times..times..times..times..times..ti-
mes..times..times..times..times..times..times..times..times..times..times.-
.times..times..times..times..times..times..times..times..times.
##EQU00001## wherein W1 is the weight value for the load C1, W2 is
the weight value for the load C2, and W3 is the weight value for
the load C3. Thus, when the current value I1 equals to about 2.6 A,
the current value I2 equals to about 9.6 A, and the current value
I3 equals to about 2.38 A, the weight value W1 is about 0.18, the
weight value W2 is about 0.66, and the weight value W3 is about
0.16.
In block S103, the summation of the load weight values W1, W2, and
W3 multiply the corresponding load voltage values V1, V2, and V3
respectively is calculated. In one embodiment, the calculation can
be denoted as follows: VD=W1*V1+W2*V2+W3*V3 (4) wherein VD is a
voltage value at an optimal point which is for sensing the VRM 200
on the PCB 100. Thus, the voltage value VD equals to about 1.46V
based on the voltage values V1, V2, V3, and the weight values W1,
W2, and W3 described above. All points with the voltage value 1.46V
on the PCB 100 can be set as the optimal points for sensing the VRM
200, and form a distributing area for the optimal points for
sensing the VRM 200.
In block S104, an optimal point for sensing the VRM 200 in the
distributing area is determined based on the layout convenience and
feasibility. The VRM 200 sets the voltage value at the optimal
point as 1.5V, which changes voltage distribution on the PCB 100.
The voltage value V1 of the load C1 becomes about 1.5062V The
voltage value V2 of the load C2 becomes about 1.4963V. The voltage
value V3 of the load C3 becomes about 1.4959V. Therefore, the
voltage margin of the load C1 becomes a difference between the new
voltage value V1 and the most voltage value about 1.575V of the VRM
200, i.e. about 68.8 mV. The voltage margin of the load C2 becomes
a difference between the new voltage value V2 and the least voltage
value about 1.425V of the VRM 200, i.e. about 71.3 mV. The voltage
margin of the load C3 becomes a difference between the new voltage
value V3 and the least voltage value about 1.425V of the VRM 200,
i.e. about 70.9 mV. It can be seen that the voltage margins of the
loads C1, C2, and C3 can be augmented by the exemplary optimization
method.
Applying the above-mentioned exemplary optimization method on a PCB
300 as shown in FIG. 3, wherein the optimal point for sensing the
VRM 200 is D1. The position of D1 is chosen because the voltage of
this point is the voltage value VD (1.46V) based on the voltage
values V1, V2, V3, and the weight values W1, W2, and W3. The PCB
300 includes a VRM 400, and three loads R1, R2, and R3. The point
D1 is located far from the VRM 400 however the point D1 may be
located on other positions of the PCB 100 depending on the voltage
value VD (1.46V), layout convenience, and feasibility. The VRM 400
provides voltage for the loads R1, R2, and R3, and sets the voltage
value at the point D1 as about 1.5V may be understood that the
voltage value about 1.5V at the point is because the voltage of the
VRM 400 is about 1.5V. After determining the point for sensing the
VRM 200, the voltage at the point is set as the voltage of the VRM
to change voltage distribution on the PCB 300 and augment the
voltage margins of the loads. That is to say, the point for sensing
the VRM further acts as a mirror voltage source of the VRM 400.
It is be understood that the VRM 400 of the PCB 300 can also be
other types of direct current sources or alternating current
sources, and the number of loads can also be adjusted. The weight
values W1, W2, and W3 can be determined by other types of weighted
average methods. For example, the weight values W1, W2, and W3 are
square normalization values of the current values I1, I2, and I3,
which can be denoted as follows:
.times..times..times..times..times..times..times..times..times..times..ti-
mes..times..times..times..times..times..times..times..times..times..times.-
.times..times..times..times..times..times..times..times..times..times..tim-
es..times..times..times..times..times..times..times..times..times..times..-
times..times..times..times..times..times..times..times..times..times..time-
s..times. ##EQU00002## or, are simple average values of the number
of the loads, which can be denoted as follows:
.times..times..times..times..times..times. ##EQU00003## wherein, n
is the number of the loads.
The foregoing description of the certain inventive embodiments of
the disclosure has been presented only for the purposes of
illustration and description and is not intended to be exhaustive
or to limit the disclosure to the precise forms disclosed. Many
modifications and variations are possible in light of the above
everything. The embodiments were chosen and described in order to
explain the principles of the disclosure and their practical
application so as to enable others of ordinary skill in the art to
utilize the disclosure and various embodiments and with various
modifications as are suited to the particular use contemplated.
Alternative embodiments will become apparent to those of ordinary
skill in the art to which the present disclosure pertains without
departing from its spirit and scope. Accordingly, the scope of the
present disclosure is defined by the appended claims rather than
the foregoing description and the embodiments described
therein.
* * * * *